Sponges suitable for use in medical procedures may include radio-opaque material, and arranged to allow individual sponges in a set, packet or package of sponges to be readily discernable using imaging technology (e.g., X-ray) to allow accurate counting of sponges. The sponges may include wireless transponders, for instance LC resonant and/or RFID transponders. Gauze or similar material is folded to enhance the ability to count the sponges. Sponges are counted and banded or packaged to provide assurance that the count is accurate.